A conventional method of introducing a transcatheter prosthetic heart valve into a patient's vasculature and toward the heart includes using a conventional introducer device to create an access port through the skin to a vein, and using a separate loader device to load a delivery catheter, with a crimped prosthetic heart valve mounted thereon, into and through the introducer device into the vasculature. The loader device typically covers the crimped heart valve with a sheath to protect it while the delivery catheter is passed through hemostatic seals in the introducer device. Covering the crimped prosthetic heart valve can reduce the risk of the crimped prosthetic heart valve migrating relative to the delivery catheter and can reduce the risk of the crimped prosthetic heart valve being damaged when it passes through the seals of the introducer device.